Step 1 - Check their arrival date
Go to the staff member's profile, click on the cog next to their contract and check their school arrival date.
If the School Arrival date has been entered as a future date, the staff member won't appear in reports.
You can amend this date if incorrect.
Step 2 - Check their profile
Staff may have been excluded from reports. You can see how to change this here: Exclude staff to hide them from reports